Number of shares issued pursuant to the terms of a deferred compensation arrangement.

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Amount of cost not yet recognized for nonvested award under share-based payment arrangement.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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No definition available.

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Weighted average remaining contractual term for option awards outstanding, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Restricted Stock, Stock Options and Other Stock Plans - Additional Information (Detail) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018	Dec. 31, 2018
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Weighted-average remaining contractual term of unexercised stock options			8 years
Unrecognized compensation cost related to stock options and restricted stock awards	$ 0.7		$ 0.7		$ 0.3
Stock Options [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares issued by the company	0	23,504	114,431	83,504
Restricted Stock Awards [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares issued by the company	12,085	0	254,336	0